Electric switch for alarms.



No. sa|,495. Patented Aug. 27, I90l.

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ELECTRIC SWITCH FOR ALARMS.

(Appliutiou and m. e, 1001.

(lo Iodel.)

UNITED STATES PATENT OFFICE.

ISRAEL B. CHANTLER, OF SEWIOKLEY, PENNSYLVANIA.

ELECTRIC S WITCH FOR ALARMS.

SPECIFICATION forming part Of Letters Patent No. 681,495, dated August 27, 1901.

Application filed March 8, 1901. Serial No. 50,375. (No model.)

To all whom it may concern:

Be it known that I, ISRAEL B. OHANTLEE, a citizen of the United States of America, residing at Sewickley, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Electric Switches for Alarms, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to certain new and useful improvements in electric switches for alarms, the object thereof being to provide an eflicient device whereby when the temperature of a room or other place is raised above a certain degree of temperature an electrical circuit will be completed to an alarm such, for instance, as an annunciator or the liketo indicate the rise in the temperature to or above the point of danger.

The invention further aims to construct a device of this character which will be extremely simple in its construction, inexpensive and durable, and adaptable for connection with the ordinary electric alarms and sources of supply now commonly employed in household use or in other instances where a device of this character may be required for indicating a rise in the temperature.

In describing the invention in detail reference is had to the accompanying drawings, forming a part of this specification, and wherein like numerals of reference indicate corresponding parts throughout the several views, in which Figure 1 is a detail side elevation of my improved switch, showing the same connected in position to a ceiling, and the electrical connections made from the switch through the battery to an alarm or annunciator, which may be located at any suitable point. Fig. 2 is a longitudinal sectional view of the switch and a part of the support therefor. Fig. 3 is a side elevation of the switch and a part of the support therefor, showing the contact closed. Fig. 4 is an underneath plan view with the contact closed. Fig. 5 is an underneath plan view of a modified form of switch. Fig. 6 is a side elevation of this modified form with the contact closed.

To put my invention into practice, I employ a resilient metallic plate 1, secured at its in nor end to a small bolt 2, which passes through a block of insulating material 8-, near one end thereof, and has its end threaded to receive a securing-nut 41- for holding the bolt in position and which also acts to bind the circuit-wire 5 upon the contact-washer 6, that is mounted on said bolt 2. One end of the metallic plate is bent at right angles to the plate and is adapted to engage the contact-plate 11. Near the opposite end of the insulating-block 3 the same carries a like bolt 7, having a threaded end to receive the nut 8, which binds the circuit-wire 9 in engagement with the contact-washer 10. The bolt 7 carries between its head and the insulating-block 3 a contact-plate 1.1, and the resilient metallic strip 1 is held normally out of contact with this plate 11 by a block 12, which is composed of any fusible substance that will melt at a certain degree of heat at which it is desired for the switch to close and complete the electrical circuit and sound the alarm. This fusible substance may be paraflin or the like, which will fuse at the temperature of about 115 Fahrenheit. A contact plateor washer 14: may be placed upon the bolt 2, between the resilient metallic strip 1 and the insulating-block 3, if desired, to assure the completion of the circuit, though this contactblock is not actually essential to the completion of such circuit. The insulating-block is attached to the ceiling, wall, or other support 15 by means of small nails 16, driven through the block near the ends of the same and into the support, the latter being recessed to receive the nuts and threaded ends of the bolts, as shown, so that the inner face of the insulating block or base will be flush with the outer face of the support. The bolts 2 and 7, together with their respective nuts, serve the function of binding-posts. I prefer to use the bolts, as herein shown, rather than the ordinary form of binding posts, as the construction is cheaper, is extremely simple, and is entirely effectual. The resilient metallic strip 1 may be provided with an opening or cut-away portion 17, as shown, at a point where the fusible block 12 bears against the strip 1, so that the heat will have freer access to the fusible block. When the temperature in the room or other place rises to a point above that at which the block 12 will fuse, the latter melts and allows the resilient strip 1 to engage and make contact with the contact-plate 11, thus completing the electrical circuit through the battery 18 to the annunciator or other alarm 19 to sound the same.

In Figs. 5 and 6 I show a modification of the device in which the fusible substance 20 is placed at each side of the contact-plate 11. The circuit is broken by moving the free end of the resilient strip 1 laterally, so that the same will engage and rise above one of the fusible blocks to hold the free end of the arm out of contact with the plate 11. Such a construction could readily be employed in connection with burglar-alarms by connecting the strip 1 to a window, door, or other object in such a manner that the opening of the same would move the arm on its pivot to disengage the same from the block 20 and allow it to contact with the plate 11. When such a device was used in case of fire, the block 20 being fusible, the same as the block 12, would allow the arm or strip 1 to contact with the plate 11, the free end of said arm not being moved over sufficiently far to prevent such engagement in case of the fusing of the block 20.

It will be observed that the strip 1 remains out of electrical connection with the contactplate 11 as long as the normal condition of atmosphere is maintained in the room or other place where the device is located; but in case of a fire, when the atmosphere is overheated, the fuse-block 12 or 20, as the case may be, will melt and allow the strip 1 to contact with the contact-plate 11 to make a circuit and sound the alarm, which will operate continuously until the battery runs out.

It will be noted that I do not wish to limit myself to the exact construction herein shown and described, as slight variations can be made in the details thereof without departing from the general spirit of my invention.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

In a device of the character described, an insulating-block, a contact-plate mounted on one end thereof, a nut and bolt for securing said plate, the underneath surface'of which is entirely in engagement with said block, a substantially rectangular fiat metallic springcontact plate having an oblong aperture formed therein, a nut and bolt for securing.

said plate at one end, the other end of said plate being bent at right angles and adapted to engage the said contact-plate, and a block of fusible material located beneath the said aperture in said plate, the said block being larger than said aperture and adapted to rest on said insulating-block, substantially as de scribed.

In testimony whereof I affix my signature in the presence of two witnesses.

ISRAEL B. OI-IANTLER.

\Vituesses:

JOHN NOLAND, A. M. WILSON. 

